This invention relates to a remote control system for a television receiver and more particularly to an interfacing system whereby a remote digitally actuated system is interfaced at the televison receiver to operate in parallel with a digital control system incorporated in the receiver. The invention is not concerned with the manner in which the television receiver selects channels and will operate with any system using digital channel selection.
It is known to use digital (push button) random selection of channel with receivers utilizing either frequency synthesis or voltage sensitive capacitor diode channel selection.
As an example of a known system utilizing remote control and voltage sensitive capacitor diode tuning, reference may be made to British Pat. No. 1,368,975--Matsushita Electric Industrial Co. Ltd. sealed Nov. 26, 1971.
In view of the trend to incorporate, in television receivers in particular, tuning systems wherein the operator selects a particular broadcast frequency by push button control whereby a required particular local oscillator frequency is generated in the receiver, either by frequency synthesis or voltage sensitive capacitor control, and mechanically switched tuners are obviated, it becomes feasible and desirable to provide a remote control facility for frequency selection and other functions. Since different methods of selecting frequencies may be used by the same or different manufacturers, it is highly desirable to provide a remote control system which may be readily interfaced with the system used on the receiver regardless of its type.